Wei Guili, Zhao Ziqiang, Du Jie, Li Pan, Sun Zhuxing, Huo Li, Gao Yongjun
Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education, College of Chemistry and Environmental Science, Hebei University Baoding 071002 Hebei China
RSC Adv. 2019 Jul 12;9(38):21715-21723. doi: 10.1039/c9ra01841g. eCollection 2019 Jul 11.
A kind of highly selective and sensitive fluorescent probe for detecting Fe, carbon dots (CDs), was prepared with renewable reed naturally containing C, N, O, and S elements as a green and eco-friendly carbon source by a simple hydrothermal process. The fluorescence of CDs without purification and surface modification can be quenched by Fe in a wide concentration range of 0 to 362 μmol L (concentration of Fe), with detection limits as low as 0.014 μmol L in 0-50 μmol L. Characterizations, such as TEM, XPS, Raman and FTIR, confirmed that the static quenching mechanism involved the generation of non-luminescent complexes between Fe and functional groups (carboxyl group, sulfur-oxyl group and hydroxyl group) on the surface of CDs and with the aggregation of CDs. More importantly, CDs had good biocompatibility and nontoxicity according to an MTT cell-viability assay, and cells labeled with CDs emitted blue, green and red color fluorescence. Thus, the static quenching mechanism was confirmed. So, this reed-derived natural CD solution can be utilized in detecting Fe, culture cells, and cell imaging.
一种用于检测铁的高选择性和灵敏性荧光探针——碳点（CDs），以天然含有碳、氮、氧和硫元素的可再生芦苇作为绿色环保的碳源，通过简单的水热法制备而成。未经纯化和表面修饰的碳点荧光可被铁在0至362微摩尔/升（铁的浓度）的宽浓度范围内猝灭，在0至50微摩尔/升范围内检测限低至0.014微摩尔/升。透射电子显微镜（TEM）、X射线光电子能谱（XPS）、拉曼光谱和傅里叶变换红外光谱（FTIR）等表征证实，静态猝灭机制涉及铁与碳点表面的官能团（羧基、硫氧基和羟基）之间形成非发光络合物以及碳点的聚集。更重要的是，根据MTT细胞活力测定，碳点具有良好的生物相容性和无毒性，用碳点标记的细胞发出蓝色、绿色和红色荧光。因此，证实了静态猝灭机制。所以，这种源自芦苇的天然碳点溶液可用于检测铁、培养细胞和细胞成像。
